Logger bros

A simple logger for fastapi with integrations for many logging tools like loki and logstash.

Features

• Super easy to use
• Dev, Full, Prod modes with sane config
• Auto generate request IDs to track logging
• Fastapi dependency injection
• Nice colors for JSON
• Fastapi dependency injection
• Loki support

Examples

Check out the quick start example in ./examples/. There are a number of other examples in ./examples/*.js.

Quick start

First add the middleware like below.

app = FastAPI()
app.add_middleware(LoggerbrosMiddleware, mode=Mode.dev)

And thats it!

You now have a nice logger. The config above also does some more magic like creating a request ID that is persisted in the logger during the whole lifecycle of the request. You will see how to use this below.

Log more like this:

@app.get("/")
async def root(logger=Depends(Logger)):

    logger.info("Hello World info")
    logger.info({"message": "json as main log"})
    logger.debug("Debuuuug", foo="foo", bar="bar")
    logger.error("Erroooor!!!", obj={"foo": "bar"}, test=test)

    return {"message": "Hello World"}

This produces the following in dev mode:

INFO:     Waiting for application startup.
INFO:     Application startup complete.
INFO:     Hello World info
INFO:     {'message': 'json as main log'}
DEBUG:    Debuuuug        {"bar": "bar", "foo": "foo"}
ERROR:    Erroooor!!!        {"obj": {"foo": "bar"}, "test": "test"}
INFO:     127.0.0.1:51995 - "GET / HTTP/1.1" 200 OK

As you can see everything passed after the first logger argument is printed in the metadata section. You can use this section for debugging info.

Running the previous example with FULL mode you get this output:

INFO:     Started server process [10912]
INFO:     Waiting for application startup.
INFO:     Application startup complete.
{
    "event": "Hello World info",
    "level": "info",
    "method": "GET",
    "request_id": "8cff8349-3d24-495b-94d3-140ec46811fc",
    "timestamp": "2022-06-20T19:42:38.527379Z",
    "url": "http://127.0.0.1:8000/"
}